GENETIC-ANALYSIS OF SHIKIMATE DEHYDROGENASE ALLOZYMES IN TRIFOLIUM-REPENS L

A genetic analysis was carried out on progeny families from pair cross es among plants polymorphic for shikimate dehydrogenase (SDH) isozymes in white clover (Trifolium repens L.). SDH was controlled by two inde pendently asserting disomic loci. This result is consistent with the p resence of a single gene (Sdh) represented in this putative allotetrap loid by one locus in each of the genomes. One of the Sdh loci is linke d (6.0 +/- 2.0 cM) to the linamarase (Li) locus. There was no evidence for differentiation of the duplicate Sdh loci (both carry common alle les). White clover behaves genetically as a diploidised allotetraploid but the possibility of a low frequency of multivalent formation and h omoeologous pairing has not been ruled out. The SDH locus is likely to be useful for the marker-assisted selection of agronomic traits.